Image forming apparatus including a movable engageable spacing member and process cartridge including a force receiving portion

Abstract

An image forming apparatus includes a mounting portion for mounting a process cartridge, the process cartridge including a first unit having an image bearing drum, and a second unit having a developing roller, the second unit being movable between a contact position in which the roller contacts the drum and a spaced position in which they are mutually spaced; an engageable member engageable with a force receiving portion provided on the second unit; wherein the engageable member is movable between a first position for maintaining the second unit in the spaced position by engaging with the force receiving portion, a second position for permitting movement of the second unit from the spaced position to the contact position; and a third position for permitting the process cartridge to be mounted, by being pressed by the process cartridge to retract, when the process cartridge is mounted to the mounting portion.

The invention claimed is: 
     
       1. An image forming apparatus comprising:
 (i) a main assembly including:
 (i-i) a spacing member, and 
 (i-ii) a movable member movable while supporting the spacing member, wherein the spacing member is movable relative to the movable member between (a) a normal position and (b) a retracted position retracted from the normal position; and 
 
 (ii) a process cartridge detachably mountable to the main assembly, the process cartridge including:
 (ii-i) a photosensitive drum, 
 (ii-ii) a developing roller movable in directions toward and away from the photosensitive drum, 
 (ii-iii) a spacing force receiving portion configured to receive a spacing force, for moving the developing roller in a direction away from the photosensitive drum, from the spacing member of the main assembly, and 
 (ii-iv) a contact portion configured to contact the spacing member to retract the spacing member, 
 
 wherein, when the spacing member is in the normal position, the spacing member is capable of applying the spacing force to the spacing force receiving portion by movement of the movable member, and 
 wherein the spacing member is retractable from the normal position to the retracted position by being contacted by the contact portion of the process cartridge. 
 
     
     
       2. An image forming apparatus according to  claim 1 , wherein the main assembly includes an urging member configured to urge the spacing member so as to move the spacing member from the retracted position to the normal position. 
     
     
       3. An apparatus according to  claim 1 , wherein the spacing member receives a force for preventing the movement thereof in a direction from the normal position toward the retracted position by engaging with the spacing force receiving portion. 
     
     
       4. An apparatus according to  claim 1 , wherein the spacing member receives a force for being urged toward the process cartridge when engaging with the spacing force receiving portion. 
     
     
       5. An apparatus according to  claim 1 , wherein the spacing member is provided with an inclined portion that (i) is inclined relative to an advancement and retracting direction of the spacing member and (ii) engages with the spacing force receiving portion, and
 wherein the inclined portion of the spacing member is inclined such that the spacing member receives a force for preventing the movement of the spacing member toward the retracted position from the spacing force receiving portion. 
 
     
     
       6. An apparatus according to  claim 1 , wherein the spacing force receiving portion is provided with an inclined portion that (i) is inclined relative to a movement direction of the spacing member and (ii) is engageable with the spacing member, and
 wherein the inclined portion of the spacing force receiving portion is inclined such that, when the inclined portion is engaged with the spacing member, the inclined portion is capable of receiving a force for preventing movement of the spacing member toward the retracted position. 
 
     
     
       7. An apparatus according to  claim 1 , wherein the spacing member receives a upward force from the spacing force receiving portion by engagement with the spacing force receiving portion. 
     
     
       8. An apparatus according to  claim 1 , wherein the movable member is reciprocable. 
     
     
       9. An apparatus according to  claim 1 , wherein by movement of the movable member from a position in which the spacing member is in contact with the contact portion of the process cartridge, the spacing member spaces from the contact portion and moves from the retracted position to the normal position. 
     
     
       10. An apparatus according to  claim 1 , wherein by movement of the movable member in one direction from a position in which the spacing member is in contact with the contact portion of the process cartridge, the spacing member spaces from the contact portion to move from the retracted position to the normal position, and thereafter, by movement of the movable member in a direction opposite to the one direction, the spacing member approaches to the spacing force receiving portion to apply the spacing force to the spacing force receiving portion. 
     
     
       11. An apparatus according to  claim 1 , wherein the spacing member is movable between the normal position and the retracted position with rotational motion relative to the movable member. 
     
     
       12. An apparatus according to  claim 1 , wherein the spacing member is movable between the normal position and the retracted position with linear motion relative to the movable member. 
     
     
       13. An apparatus according to  claim 1 , wherein the spacing member is movable downwardly from the normal position to the retracted position. 
     
     
       14. An apparatus according to  claim 1 , wherein the process cartridge includes a first unit having the photosensitive drum, a second unit having the developing roller, and
 wherein the second unit is movable relative to the first unit in the direction of moving the developing roller away from the photosensitive drum by the spacing force receiving portion receiving the spacing force. 
 
     
     
       15. An image forming apparatus according to  claim 1 , wherein the main assembly includes a cartridge holding member configured to hold the process cartridge and to move the process cartridge from outside of the main assembly to inside of the main assembly. 
     
     
       16. An apparatus according to  claim 1 , wherein the image forming apparatus comprises a plurality of such process cartridges, and
 wherein the main assembly includes such spacing members corresponding to respective process cartridges. 
 
     
     
       17. An image forming apparatus comprising:
 (i) a main assembly including:
 (i-i) a spacing member; and 
 
 (ii) a process cartridge detachably mountable to the main assembly, the process cartridge including:
 (ii-i) a photosensitive drum, 
 (ii-ii) a developing roller movable in a direction toward and away from the photosensitive drum, 
 (ii-iii) a spacing force receiving portion configured to receive a spacing force, for moving the developing roller away from the photosensitive drum, from the spacing member of the main assembly, and 
 (ii-iv) a contact portion configured to contact the spacing member to retract the spacing member, 
 
 wherein the spacing member is movable between three different positions which are:
 (a) a first position for applying the spacing force to the spacing force receiving portion to move the developing roller in a direction away from the photosensitive drum, 
 (b) a second position deviated from the first position in a direction away from the spacing force receiving portion to permit the developing roller to approach to the photosensitive drum, and 
 (c) a third position that is a retracted position provided by contacting the contact portion to avoid interference with the process cartridge. 
 
 
     
     
       18. An apparatus according to  claim 17 , wherein the main assembly includes a movable member movable while supporting the spacing member, and
 wherein the spacing member is movable relative to the movable member in advancing and retracting directions. 
 
     
     
       19. An apparatus according to  claim 18 , wherein the movable member is reciprocable. 
     
     
       20. An apparatus according to  claim 18 , wherein the spacing member is movable between a normal position and the retracted position relative to the movable member in the advancing and retracting directions,
 wherein the spacing member is movable between the first position and the second position, by movement of the movable member in a state in which the spacing member is in the normal position with respect to the movable member, and 
 wherein, when the spacing member is in the third position, the spacing member is in the retracted position with respect to the movable member. 
 
     
     
       21. An apparatus according to  claim 17 , wherein the spacing member is retracted to the third position in a direction different from a direction of movement of the spacing member between the first position and the second position. 
     
     
       22. An apparatus according to  claim 17 , wherein the main assembly includes an urging member configured to urge the spacing member from the third position toward the process cartridge. 
     
     
       23. An apparatus according to  claim 17 , wherein the spacing member receives a force for pulling the spacing member toward the process cartridge when engaging with the spacing force receiving portion. 
     
     
       24. An apparatus according to  claim 17 , wherein the spacing member is provided with an inclined portion that is engageable with the spacing force receiving portion, and
 wherein the inclined portion of the spacing member is inclined such that when the inclined portion of the spacing member engages with the spacing force receiving portion, the spacing member receives a force for pulling the spacing member toward the process cartridge from the spacing force receiving portion. 
 
     
     
       25. An apparatus according to  claim 17 , wherein the spacing force receiving portion is provided with an inclined portion that is engageable with the spacing member, and
 wherein the inclined portion of the spacing force receiving portion is inclined so as to pull the spacing member toward the process cartridge when the inclined portion of the spacing force receiving portion engages with the spacing member. 
 
     
     
       26. An apparatus according to  claim 17 , wherein the spacing member receives an upward force from the spacing force receiving portion by engagement with the spacing force receiving portion. 
     
     
       27. An apparatus according to  claim 17 , wherein the spacing member is movable from the third position to the first position by way of the second position. 
     
     
       28. An apparatus according to  claim 17 , wherein the spacing member is movable from the third position to the second position by movement of the spacing member away from the contact portion, and thereafter, the spacing member is movable from the second position to the first position to approach to the spacing force receiving portion. 
     
     
       29. An apparatus according to  claim 17 , wherein the spacing member is retracted to the third position with rotational motion when contacting the contact portion. 
     
     
       30. An apparatus according to  claim 17 , wherein the spacing member is retracted to the third position with linear motion when contacting the contact portion. 
     
     
       31. An apparatus according to  claim 17 , wherein the third position is below the first position. 
     
     
       32. An apparatus according to  claim 17 , wherein the process cartridge includes a first unit having the photosensitive drum, a second unit having the developing roller, and
 wherein the second unit is movable relative to the first unit in the direction of moving the developing roller in a direction away from the photosensitive drum by the spacing force receiving portion receiving the spacing force. 
 
     
     
       33. An image forming apparatus according to  claim 17 , wherein the main assembly includes a cartridge holding member configured to move the process cartridge from outside of the main assembly to inside of the main assembly in a state of holding the process cartridge. 
     
     
       34. An apparatus according to  claim 17 , wherein the apparatus includes a plurality of such process cartridges, and
 wherein the main assembly includes a plurality of such spacing members corresponding to respective process cartridge.